Many people are choosing this winter to replace their older...

Many people are choosing this winter to replace their older furnace and invest in a high-efficiency furnace. Some of today's furnaces have an efficiency rating of 94.2 percent. That means, for every dollar you spend on gas, nearly 95 cents worth is heating your home. If you furnace is15 to 20 years old, the efficiency could be as low as 65 to 70 percent.